1. Field of the Invention
This invention is directed to a system which allows effective inventory control and extensive tracking capabilities of a plurality of articles by providing total real time access to a monitored locale in order to establish the existence, location and/or direction of movement of the articles. A plurality of tags are associated with the various articles being monitored, at least some of which include multi-frequency and uni-directional or multi-directional communication capabilities which at least partially serve to extend the operative range between the tags and a reader assembly in order to efficiently perform the monitoring procedure.
2. Description of the Related Art
The monitoring of a variety of different articles, products, etc. through the use of “tags” secured to or otherwise associated with the various articles has been in use for many years. Moreover, various attempts to modify this type of tracking and inventory control have been made so as to adapt a tagging system for use in a variety of different applications. Such known applications include, but are not limited to, warehouses, retail outlets, industrial manufacturing sites, and almost any location where the variety or articles or products being monitored are manufactured, transported, stored, sold, etc.
In its more simplistic form, the tagging of articles has been associated with the display of pricing information in association with the shelving of various products, such as in retail outlets. Pricing and inventory controls are sometimes maintained through the inclusion of coded data on the tags, such as by means of bar codes, which are determinative of the identity, price, etc, of the various products. Initially, and as is currently being used, these types of “shelf tags” have been simply constructed and include various information displayed thereon. Such displayed information, when coded as set forth above, can be read by various types of optical or digital scanners.
While shelf tags of the type set forth above are generally considered to be operative for less sophisticated applications, they are commonly recognized as being inefficient and cumbersome for use in many areas of commerce associated with the storage, transport, manufacture, etc, of various types of products or articles being monitored. As one example, the updating the information frequently requires complete replacement of the tags thereby at least partially defeating the goal of efficient inventory, tracking and pricing controls for which such systems were primarily intended.
To overcome the above noted problems associated with shelf tags, attempts have been made to develop more sophisticated electronic tags which are associated with some type of display facilities. Typically known electronic tags and their attendant systems, of the type referred to wherein require the use of complicated circuitry and cooperative electronic control components in order to affect their installation and use. Another major draw back associated with devices of this type is that in order to maintain an efficient and accurate display a continuous supply of power must be maintained. The maintenance of such power is limited resulting in the limiting of information which can reasonably be displayed. Accordingly frequent replacement of the tags, associated power supplies, display facilities, etc, is the result.
In an effort to expand the versatility and efficiency of tracking and inventory control of a variety of articles, products, etc. and as a result of the problems and disadvantages of the type set forth above, associated industries have moved forward. Resulting advancements in this field has yielded the development and utilization of radio frequency (RF) tags and their attendant systems. In general, RF tags are capable of retaining and transmitting a substantial amount of information, all of which is required for the expansive tracking, security and inventory control requirements associated with modern day industrial, transport and retail facilities.
More specifically, the RF tag systems are capable of receiving and storing information in a read/write application as well as being capable of sending and/or receiving data relating to product identification, status, location and overall control. However, known or conventional RF tagging systems are recognized as having at least one primary disadvantage associated with limited communication range. Accordingly, in order that transmission of signals to one or more tags be accomplished for purposes of activation and/or data communication, an appropriate exciter/reader would have to be positioned in very close proximity to the one or more tags involved in the monitoring system. Therefore, the versatility and practical applications of such systems are severely limited due at least to the proximity or range restrictions associated therewith. Efficient monitoring of articles during product delivery, transportation, material handling, security tracking and large scale storage may not be possible. As a result, radio frequency tag technology has not enjoyed wide spread use in many industrial applications associated with the commercial development of various products.
Based on the above, there are still significant disadvantages and problems associated with known tagging systems especially when considering the wide variety of industrial applications where such systems could be effectively implemented. Accordingly, there is a significant and long recognized need for an improved tracking and/or inventory control system. Such an improved system should be capable of 100% real time inventory control as well as detecting the existence, location and direction of movement of an item being monitored. A plurality of RF tags associated with such an improved system could be further structured to detect tampering, low battery power, unauthorized movement and/or removal of the tags from the articles or products being monitored.
Such an improved system could also be adapted, without significant structural or operative modification, for usage in a variety of different areas including large scale warehousing, transport, delivery, retail inventory, pricing and security, theft prevention, all without significant manual intervention. In addition, other unique and/or customized features can be associated with the tags, dependent on the customer/user applications and requirements.
Accordingly, an improved system using multi frequency tags with strategically placed readers, accomplishing activation and/or powering of certain ones of the plurality of tags utilizing a higher level of power signal and prescribed frequency range would increase the reading or transmission distance associated with the tags. Such an improved system would overcome the recognized problems and disadvantages associated with RF tag monitoring systems of the type set forth above.